# US 8,739,947 B2 · Brake lining for a drum brake assembly > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,739,947 B2 - Document ID: US8739947B2 - Status: Granted - Kind: B2 - Application number: 13/307,563 - Filed: 2011-11-30 - Published: 2013-05-30 - Granted: 2014-06-03 - Earliest claimed: 2011-11-30 - Assignees: Federal-Mogul Products, Inc. - Applicants: Weiming Liu - Inventors: Weiming Liu - Web page: https://patentgrep.com/patent/US8739947B2 ## CPC - F16D 65/08: for internally-engaging brakes - F16D 51/20: extending in opposite directions from their pivots - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES ## Abstract An improved drum brake assembly for reducing braking vibrations and noise. The improved assembly includes a pair of shoes, each extending through an arc and presenting an outer shoe surface. A pair of brake linings of a friction material are coupled to the outer shoe surface. Each of the brake linings has an upper surface and a pair of oppositely facing chamfered edges. Each chamfered edge has an arc length of no less than one inch and is disposed at an angle of between ten and twenty-five degrees from the tangent of the upper surface where it meets the chamfered edge. ## Claims ### Claim 1 A brake lining for a drum brake assembly of a heavy-duty vehicle comprising: said brake lining being of a friction material and having an upper surface and presenting a pair of oppositely facing chamfered edges which extend through less than an entire thickness of said brake lining, and wherein said oppositely facing chamfered edges are the only chamfered edges on said brake lining and comprise between twenty-five and thirty-five percent of the arcuate length of said brake lining and wherein each of said chamfered edges is disposed at an angle of between ten and twenty-five degrees from the tangent of said upper surface where it meets said chamfered edge. ### Claim 2 (depends on 1) The brake lining of claim 1 wherein said brake lining is generally arcuately shaped. ### Claim 3 (depends on 2) The brake lining of claim 2 wherein each of said chamfered edges has a length of no less than one inch. ### Claim 4 (depends on 1) The brake lining of claim 1 wherein said opposite chamfered edges are disposed at different angles relative to the top surface than one another. ### Claim 5 A shoe for a drum brake assembly of a heavy-duty vehicle comprising: said shoe extending through an arc and presenting an outer shoe surface; at least one brake lining coupled to said outer shoe surface and being of a friction material; said brake lining having an upper surface and presenting a pair of oppositely facing chamfered edges which extend through less than an entire thickness of said brake lining; and wherein said oppositely facing chamfered edges are the only chamfered edges on said brake lining and comprise between twenty-five and thirty-five percent of the arcuate length of said brake lining and wherein each of said chamfered edges is disposed at an angle of between ten and twenty-five degrees from the tangent of said upper surface where it meets said chamfered edge. ### Claim 6 (depends on 5) The shoe as set forth in claim 5 wherein said brake lining is generally arcuately shaped. ### Claim 7 (depends on 6) The shoe as set forth in claim 6 wherein each of said chamfered edges has a length of no less than one inch. ### Claim 8 (depends on 5) The shoe as set forth in claim 5 further including a pair of brake linings disposed adjacent to one another on said outer shoe surface. ### Claim 9 (depends on 8) The shoe as set forth in claim 8 wherein each of said brake linings includes a first chamfered edge disposed at a first angle from the tangent of said upper surface where it meets said first chamfered edge and a second chamfered edge disposed at a second angle from the tangent of said upper surface where it meets said second chamfered edge. ### Claim 10 (depends on 9) The shoe as set forth in claim 9 wherein said first angle of said first chamfered edge is different than said second angle of said second chamfered edge. ### Claim 11 (depends on 10) The shoe as set forth in claim 10 wherein said first chamfered edges of adjacent brake linings face towards one another and said second chamfered edges of adjacent brake linings face away from one another. ### Claim 12 (depends on 11) The shoe as set forth in claim 11 wherein said first angles of said first chamfered edges are greater than said second angles of said second chamfered edges. ### Claim 13 A drum brake assembly for slowing a vehicle having a drum with a circular drum surface comprising: a pair of shoes, each extending through an arc and presenting an outer shoe surface; at least one brake lining coupled to at least one of said outer shoe surfaces and being of a friction material; said brake lining having an upper surface and presenting a pair of oppositely facing chamfered edges which extend through less than the entire thickness of said brake lining; and wherein said oppositely facing chamfered edges are the only chamfered edges on said brake lining and comprise between twenty-five and thirty-five percent of the arcuate length of said brake lining and wherein each of said chamfered edges is disposed at an angle of between ten and twenty-five degrees from the tangent of said upper surface where it meets said chamfered edge. ### Claim 14 (depends on 13) The drum brake assembly as set forth in claim 13 wherein said brake lining is generally arcuately shaped. ### Claim 15 (depends on 14) The drum brake assembly as set forth in claim 14 wherein each of said chamfered edges has a length of no less than one inch. ### Claim 16 (depends on 13) The drum brake assembly as set forth in claim 13 said at least one brake lining includes a pair of linings disposed adjacent to one another on said outer shoe surface. ### Claim 17 (depends on 16) The drum brake assembly as set forth in claim 16 wherein each of said brake linings includes a first chamfered edge disposed at a first angle from the tangent of said upper surface where it meets said first chamfered edge and a second chamfered edge disposed at a second angle from the tangent of said upper surface where it meets said second chamfered edge. ### Claim 18 (depends on 17) The drum brake assembly as set forth in claim 17 wherein said first angle of said first chamfered edge is different than said second angle of said second chamfered edge. ### Claim 19 (depends on 18) The drum brake assembly as set forth in claim 18 wherein said first chamfered edges of adjacent brake linings face towards one another and said second chamfered edges of adjacent brake linings face away from one another. ### Claim 20 (depends on 19) The drum brake assembly as set forth in claim 19 wherein said first angles of said first chamfered edges are greater than said second angles of said second chamfered edges.